A higher body mass index (BMI) increases the risk of developing 10 of the most common cancers, the largest study of its kind published in the latest issue of scientific journal The Lancet has showed.

British researchers at the London School of Hygiene and Tropical Medicine estimated that over 12 000 British cases of these 10 cancers each year are attributable to being overweight or obese.

Using data from general practitioner records in Britain, the researchers identified 5.24 million individuals aged 16 and over who were cancer-free and had been followed for an average of 7.5 years.

The risk of developing 22 of the most common cancers, which represent 90 percent of the cancers diagnosed in Britain, was measured according to BMI after adjusting for individual factors such as age, sex, smoking status, and socioeconomic status.

A total of 166 955 people developed cancer over the follow-up period.

The study found that, each 5 kg/m? increase in BMI was clearly linked with higher risk of cancers of the uterus, gallbladder, kidney, cervix, thyroid, and leukaemia.

"The number of people who are overweight or obese is rapidly increasing both in the UK and worldwide," study leader Dr Krishnan Bhaskaran said.

"It is well recognised that this is likely to cause more diabetes and cardiovascular disease. Our results show that if these trends continue, we can also expect to see substantially more cancers as a result," he addied.